This invention relates to a novel group of guanidine compounds, processes for the preparation thereof, the use thereof in treating IL-8, GROxcex1, GROxcex2, GROxcex3, NAP-2, and ENA-78 mediated diseases and pharmaceutical compositions for use in such therapy.
Many different names have been applied to Interleukin-8 (IL-8), such as neutrophil attractant/activation protein-1 (NAP-1), monocyte derived neutrophil chemotactic factor (MDNCF), neutrophil activating factor (NAF), and T-cell lymphocyte chemotactic factor. Interleukin-8 is a chemoattractant for neutrophils, basophils, and a subset of T-cells. It is produced by a majority of nucleated cells including macrophages, fibroblasts, endothelial and epithelial cells exposed to TNF, IL-1xcex1, IL-1xcex2 or LPS, and by neutrophils themselves when exposed to LPS or chemotactic factors such as FMLP. M. Baggiolini et al, J. Clin. Invest. 84, 1045 (1989); J. Schroder et al, J. Immunol. 139, 3474 (1987) and J. Immunol. 144, 2223 (1990); Strieter, et al, Science 243, 1467 (1989) and J. Biol. Chem. 264, 10621 (1989); Cassatella et al, J. Immunol. 148, 3216 (1992).
Groxcex1, GROxcex2, GROxcex3 and NAP-2 also belong to the chemokine xcex1 family. Like IL-8 these chemokines have also been referred to by different names. For instance GROxcex1, xcex2, xcex3 have been referred to as MGSAxcex1, xcex2 and xcex3 respectively (Melanoma Growth Stimulating Activity), see Richmond et al, J. Cell Physiology 129, 375 (1986) and Chang et al, J. Immunol 148, 451 (1992). All of the chemokines of the xcex1-family which possess the ELR motif directly preceding the CXC motif bind to the IL-8 B receptor.
IL-8, Groxcex1, GROxcex2, GROxcex3, NAP-2 and ENA-78 stimulate a number of functions in vitro. They have all been shown to have chemoattractant properties for neutrophils, while IL-8 and GROxcex1 have demonstrated T-lymphocytes, and basophiles chemotactic activity. In addition IL-8 can induce histamine release from basophils from both normal and atopic individuals. GRO-xcex1 and IL-8 can in addition, induce lysozomal enzyme release and respiratory burst from neutrophils. IL-8 has also been shown to increase the surface expression of Mac-1 (CD11b/CD18) on neutrophils without de novo protein synthesis. This may contribute to increased adhesion of the neutrophils to vascular endothelial cells. Many known diseases are characterized by massive neutrophil infiltration. As IL-8, Groxcex1, GROxcex2, GROxcex3 and NAP-2 promote the accumulation and activation of neutrophils, these chemokines have been implicated in a wide range of acute and chronic inflammatory disorders including psoriasis and rheumatoid arthritis, Baggiolini et al, FEBS Lett. 307, 97 (1992); Miller et al, Crit. Rev. Immunol. 12, 17 (1992); Oppenheim et al, Annu. Rev. Immunol. 9, 617 (1991); Seitz et al., J. Clin. Invest. 87, 463 (1991); Miller et al., Am. Rev. Respir. Dis. 146, 427 (1992); Donnely et al., Lancet 341, 643 (1993). In addition the ELR chemokines (those containing the amino acids ELR motif just prior to the CXC motif) have also been implicated in angiostasis, Strieter et al, Science 258, 1798 (1992).
In vitro, IL-8, Groxcex1, GROxcex2, GROxcex3, and NAP-2 induce neutrophil shape change, chemotaxis, granule release, and respiratory burst, by binding to and activating receptors of the seven-transmembrane, G-protein-linked family, in particular by binding to IL-8 receptors, most notably the B-receptor, Thomas et al., J. Biol. Chem. 266, 14839 (1991); and Holmes et al., Science 253, 1278 (1991). The development of non-peptide small molecule antagonists for members of this receptor family has precedent. For a review see R. Freidinger in: Progress in Drug Research, Vol. 40, pp. 33-98, Birkhauser Verlag, Basel 1993. Hence, the IL-8 receptor represents a promising target for the development of novel anti-inflammatory agents.
Two high affinity human IL-8 receptors (77% homology) have been characterized: IL-8Rxcex1, which binds only IL-8 with high affinity, and IL-8RB, which has high affinity for IL-8 as well as for GRO-xcex1, GROxcex2, GROxcex3 and NAP-2. See Holmes et al., supra; Murphy et al., Science 253, 1280 (1991); Lee et al., J. Biol. Chem. 267, 16283 (1992); LaRosa et al., J. Biol. Chem. 267, 25402 (1992); and Gayle et al., J. Biol. Chem. 268, 7283 (1993).
There remains a need for treatment, in this field, for compounds which are capable of binding to the IL-8 xcex1 or xcex2 receptor. Therefore, conditions associated with an increase in IL-8 production (which is responsible for chemotaxis of neutrophil and T-cells subsets into the inflammatory site) would benefit by compounds which are inhibitors of IL-8 receptor binding.
This invention provides for a method of treating a chemokine mediated disease, wherein the chemokine is one which binds to an IL-8 xcex1 or xcex2 receptor and which method comprises administering an effective amount of a compound of Formula (I) or a pharmaceutically acceptable salt thereof. In particular the chemokine is IL-8.
This invention also relates to a method of inhibiting the binding of IL-8 to its receptors in a mammal in need thereof which comprises administering to said mammal an effective amount of a compound of Formula (I).
Compounds of Formula (I) useful in the present invention are represented by the structure 
wherein:
R is OH, SH, NHSO2Rd;
Rd is NR6R7, alkyl, arylC1-4alklyl, arylC2-4 alkenyl, heteroaryl, hetroaryl-C1-4alkyl, heteroarylC2-4 alkenyl, heterocyclic, heterocyclicC1-4 alkyl, wherein the aryl, heteoaryl and heterocyclic rings may all be optionally substituted,
R6 and R7 are independently hydrogen, or a C1-4 alkyl group, or R6 and R7 together with the nitrogen to which they are attached form a 5 to 7 member ring which ring may optionally contain an additional heteroatom is selected from oxygen, nitrogen or sulfur, and which ring may be optionally substituted;
R1 is independently selected from hydrogen; halogen; nitro; cyano; halosubstituted C1-10 alkyl, C1-10 alkyl, C2-10 alkenyl, C1-10 alkoxy, halosubstituted C1-10 alkoxy, azide, (CR8R8)qS(O)tR4, hydroxy, hydroxy C1-4alkyl, aryl, aryl C1-4 alkyl, aryloxy, aryl C1-4 alkyloxy, heteroaryl, heteroarylalkyl, heterocyclic, heterocyclic C1-4alkyl, heteroaryl C1-4 alkyloxy, aryl C2-10 alkenyl, heteroaryl C2-10 alkenyl, heterocyclic C2-10 alkenyl, (CR8R8)qNR4R5, C2-10 alkenyl C(O)NR4R5, (CR8R8)qC(O)NR4R5, (CR8R8)qC(O)NR4R10, S(O)3H, S(O)3R8, (CR8R8)qC(O)R11, C2-10 alkenyl C(O)R11, C2-10 alkenyl C(O)OR11(CR8R8)qC(O)OR12, (CR8R8)qOC(O)R11, (CR8R8)qNR4C(O)R11, (CR8R8)qNHS(O)2R17, (CR8R8)qS(O)2NR4R5, or two R1 moieties together may form Oxe2x80x94(CH2)sOxe2x80x94 or a 5 to 6 membered unsaturated ring;
R2 is independently selected from C2-5alkyl and C2-5alkenyl all of which moieties may be optionally substituted one to three times independently by halogen; nitro; halosubstituted C1-4 alkyl; C1-4 alkyl; amino, mono or di-C1-4 alkyl substituted amine; hydroxy; C1-4 alkoxy; NR9C(O)Ra; S(O)mRa; C(O)NR6R7; C(O)OH; C(O)ORa; S(O)2NR6R7; NHS(O)2Ra; and optionally containing, in addition to carbon, independently, 1 to 3 NR9, O, C(O), S, SO, or SO2 moities.
R3 is independently selected from C1-10 alkyl; halosubstituted C1-10 alkyl; C2-10 alkenyl; C1-10 alkoxy; halosubstituted C1-10alkoxy; azide; S(O)tR4; (CR8R8)qS(O)tR4; hydroxy; hydroxy substituted C1-4alkyl; aryl; aryl C1-4 alkyl; aryl C2-10 alkenyl; aryloxy; aryl C1-4 alkyloxy; heteroaryl; heteroarylalkyl; heteroaryl C2-10 alkenyl; heteroaryl C1-4 alkyloxy; heterocyclic, heterocyclic C1-4alkyl; heterocyclicC1-4alkyloxy; heterocyclicC2-10 alkenyl; (CR8R8)qNR4R5; (CR8R8)qC(O)NR4R5; C2-10 alkenyl C(O)NR4R5; (CR8R8)qC(O)NR4R10; S(O)3R8; (CR8R8)qC(O)R11; C2-10 alkenyl C(O)R11; C2-10 alkenyl C(O)OR11; (CR8R8)qC(O)OR11; (CR8R8)qOC(O)R11; (CR8R8)qNR4C(O)R11; (CR8R8)qC(NR4)NR4R5; (CR8R8)qNR4C(NR5)R11; (CR8R8)qNHS(O)2R12; (CR8R8)qS(O)2NR4R5; or two R1 moieties together may form Oxe2x80x94(CH2)sO or a 5 to 6 membered saturated or unsaturated ring, and wherein the alkyl, aryl, arylalkyl, heteroaryl, heterocyclic moieties may be optionally substituted;
q is 0, or an integer having a value of 1 to 10;
t is 0, or an integer having a value of 1 or 2;
s is an integer having a value of 1 to 3;
R4 and R5 are independently hydrogen, optionally substituted C1-4 alkyl, optionally substituted aryl, optionally substituted aryl C1-4alkyl, optionally substituted heteroaryl, optionally substituted heteroaryl C1-4alkyl, heterocyclic, heterocyclicC1-4 alkyl, or R4 and R5 together with the nitrogen to which they are attached form a 5 to 7 member ring which may optionally comprise an additional heteroatom selected from oxygen, nitrogen or sulfur;
Y is independently selected from hydrogen; halogen; nitro; cyano; halosubstituted C1-10 alkyl, C1-10 alkyl, C2-10 alkenyl, C1-10 alkoxy, halosubstituted C1-10 alkoxy, azide, (CR8R8)qS(O)tR4, hydroxy, hydroxyC1-4alkyl, aryl, aryl C1-4 alkyl, aryloxy, arylC1-4 alkyloxy, heteroaryl, heteroarylalkyl, heteroaryl C1-4 alkyloxy; heterocyclic, heterocyclic C1-4alkyl, aryl C2-10 alkenyl, heteroaryl C2-10 alkenyl, heterocyclic C2-10 alkenyl, (CR8R8)qNR4R5, C2-10 alkenyl C(O)NR4R5, (CR8R8)qC(O)NR4R5, (CR8R8)qC(O)NR4R10, S(O)3H, S(O)3R8, (CR8R8)qC(O)R11, C2-10 alkenyl C(O)R11, C2-10 alkenyl C(O)OR11, C(O)R11, (CR8R8)qC(O)OR12, (CR8R8)qOC(O)R11, (CR8R8)qNR4C(O)R11, (CR8R8)qNHS(O)2Rd, (CR8R8)qS(O)2NR4R5, or two Y moieties together may form Oxe2x80x94(CH2)sOxe2x80x94 or a 5 to 6 membered unsaturated ring,
n is an integer having a value of 1 to 3,
m is an integer having a value of 1 to 3,
R8 is hydrogen or C1-4 alkyl,
R9 is hydrogen or a C1-4 alkyl,
R10 is C1-10 alkyl C(O)2R8,
R11 is hydrogen, C1-4 alkyl, optionally substituted aryl, optionally substituted aryl C1-4alkyl, optionally substituted heteroaryl, optionally substituted heteroarylC1-4alkyl, optionally substituted heterocyclic, or optionally substituted heterocyclicC1-4alkyl,
R12 is hydrogen, C1-10 alkyl, optionally substituted aryl or optionally substituted arylalkyl;
R17 is C1-4alkyl, aryl, arylalkyl, heteroaryl, heteroarylC1-4alkyl, heterocyclic, or heterocyclicC1-4alkyl, wherein the aryl, heteroaryl and heterocyclic rings may all be optionally substituted; and
Ra is an alkyl, aryl, arylC1-4alkyl, heteroaryl, heteroaryl C1-4alkyl, heterocyclic, or a heterocyclic C1-4alkyl moiety, all of which moieties may be optionally substituted.
The compounds of Formula (I) may also be used in association with the veterinary treatment of mammals, other than humans, in need of inhibition of IL-8 or other chemokines which bind to the IL-8RA and RB receptors. Chemokine mediated diseases for treatment, therapeutically or prophylactically, in animals include disease states such as those noted herein in the Methods of Treatment section.
Preferred compounds useful in the present invention include:
4-[[3-(2-bromophenyl)-4-oxo-1-(phenylmethyl)-2-imidazolidinylidene]imino]-3-hydroxybenzonitrile;
4-[[(7aS)-2-(2-bromophenyl)-hexahydro-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile;
4-[[5-(2-bromophenyl)-3,3a,4,5-tetrahydro-1,1-dioxido-4-oxoimidazo[1,5-b]isothiazol-6(2H)-ylidene]amino]-3-hydroxybenzonitrile;
4-[[(6R,7aS)-2-(2-bromophenyl)-hexahydro-6-hydroxy-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile;
4-[[(7aR)-2-(2-bromophenyl)-hexahydro-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile,
4-[(S)-2-(2,3-Dichloro-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile,
4-[(R)-2-(2,3-Dichloro-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile,
4-[2-(2,3-Dichloro-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile,
4-[(S)-2-(2-Bromo-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile,
4-[(R)-2-(2-Bromo-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile,
4-[2-(2-Bromo-phenyl)-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-3-ylideneamino]-3-hydroxy-benzonitrile, and
4-[[2-(2-bromophenyl)-1,5,6,7,8,8a-hexahydro-1-oxoimidazo[1,5-a]pyridin-3(2H)-ylidene]amino]-3-hydroxybenzonitrile; or a pharmaceutically acceptable salt thereof.
Suitable pharmaceutically acceptable salts are well known to those skilled in the art and include basic salts of inorganic and organic acids, such as hydrochloric acid, hydrobromic acid, sulphuric acid, phosphoric acid, methane sulphonic acid, ethane sulphonic acid, acetic acid, malic acid, tartaric acid, citric acid, lactic acid, oxalic acid, succinic acid, fumaric acid, maleic acid, benzoic acid, salicylic acid, phenylacetic acid and mandelic acid. In addition, pharmaceutically acceptable salts of compounds of Formula (I) may also be formed with a pharmaceutically acceptable cation, for instance, if a substituent group comprises a carboxy moiety. Suitable pharmaceutically acceptable cations are well known to those skilled in the art and include alkaline, alkaline earth, ammonium and quaternary ammonium cations.
The following terms, as used herein, refer to:
xe2x80x9chaloxe2x80x9dxe2x80x94all halogens, that is chloro, fluoro, bromo and iodo.
xe2x80x9cC2-5alkylxe2x80x9d or xe2x80x9calkylxe2x80x9dxe2x80x94both straight and branched chain moieties of 2 to 5 carbon atoms, unless the chain length is otherwise limited, including, but not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl and the like.
The term xe2x80x9calkenylxe2x80x9d is used herein at all occurrences to mean straight or branched chain moieties of 2-10 carbon atoms, unless the chain length is limited thereto, including, but not limited to ethenyl, 1-propenyl, 2-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl and the like.
xe2x80x9carylxe2x80x9dxe2x80x94phenyl and naphthyl;
xe2x80x9cheteroarylxe2x80x9d (on its own or in any combination, such as xe2x80x9cheteroaryloxyxe2x80x9d, or xe2x80x9cheteroaryl alkylxe2x80x9d)xe2x80x94a 5-10 membered aromatic ring system in which one or more rings contain one or more heteroatoms selected from the group consisting of N, O or S, such as, but not limited, to pyrrole, pyrazole, furan, thiophene, quinoline, isoquinoline, quinazolinyl, pyridine, pyrimidine, oxazole, thiazole, thiadiazole, triazole, imidazole, or benzimidazole.
xe2x80x9cheterocyclicxe2x80x9d (on its own or in any combination, such as xe2x80x9cheterocyclicalkylxe2x80x9d)xe2x80x94a saturated or partially unsaturated 4-10 membered ring system in which one or more rings contain one or more heteroatoms selected from the group consisting of N, O, or S; such as, but not limited to, pyrrolidine, piperidine, piperazine, morpholine, tetrahydropyran, or imidazolidine.
The term xe2x80x9carylalkylxe2x80x9d or xe2x80x9cheteroarylalkylxe2x80x9d or xe2x80x9cheterocyclicalkylxe2x80x9d is used herein to mean C1-10 alkyl, as defined above, attached to an aryl, heteroaryl or heterocyclic moiety, as also defined herein, unless otherwise indicated.
The compounds of Formula (I) may be obtained by applying synthetic procedures, some of which are illustrated in the Schemes below. The synthesis provided for in these Schemes is applicable for producing compounds of Formula (I) having a variety of different R, R1, and aryl groups which are reacted, employing optional substituents which are suitably protected, to achieve compatibility with the reactions outlined herein. Subsequent deprotection, in those cases, then affords compounds of the nature generally disclosed. Once the guanidine nucleus has been established, further compounds of these formulas may be prepared by applying standard techniques for functional group interconversion, well known in the art. While the schemes are shown with compounds only of Formula (I) this is merely for illustration purposes only. 
The desired aniline 6-scheme-1 can be prepared from the commercially available benzoxazolinone 1-scheme-1. Bromide 2-scheme-1 can be prepared from benzoxazolinone 1-scheme-1 using standard bromination conditions such as bromine and sodium acetate in acetic acid. Bromide 2-scheme-1 can be converted to the cyanide 3-scheme-1 using standard procedures such as copper (I) cyanide in refluxing DMF. The amide 3-scheme-1 can be converted to the BOC protected compound 4-scheme-1 using standard conditions such as BOC anhydride and triethylamine with a catalytic amount of dimethylaminopyridine in methylene chloride or another suitable organic solvent. The oxazolinone 4-scheme-1 can be converted to the desired aniline 6-scheme-1 by first hydrolysis to the phenol 5-scheme-1 using standard conditions such as potassium carbonate in methanol followed by removal of the BOC protecting group using standard conditions such as trifluoroacetic acid in methylene chloride or another suitable organic solvent to give the aniline 6-scheme-1. 
The desired thiourea 3-scheme-2 can be prepared as outlined in scheme 2. The aniline 1-scheme-2 can be coupled with a commercially available isothiocyanate or with an isothiocyanate made from condensing a commercially available amine with thiophosgene or a thiophosgene equivalent to give the thiourea 2-scheme-2. The phenol 2-scheme-2 can be protected as the TBS ether 3-scheme-2 using standard conditions such as TBSCl and imidazole in THF or another suitable organic solvent. Alternatively the amine 1-scheme-2 can be converted to the isothiocyanate 5-Scheme-2 by first protecting the phenol 1-Scheme-2 with a suitable protecting group such as the TBS ether 4-scheme-2 using standard conditions such as TBSCl and an amine base such as imidazole in THF or another suitable organic solvent. The thiourea 5-scheme-2 can be made by condensing the amine 4-scheme 2 with thiophosgene in the presence of a base such as potassium carbonate. The desired thiourea 3-scheme-2 can be prepared from the isothiocyanate 5-scheme-2 by condensing it with the desired amine in a suitable organic solvent such as ethanol or DMF. 
The desired lactam 3-scheme-3 can be prepared as outlined in Scheme 3. The carbodiimide 2-Scheme-3 can be prepared from the thiourea 1-scheme-3 using standard conditions such as an excess amount of methane sulfonyl chloride and a suitable amine base such as triethylamine in an organic solvent preferably methylene chloride at room temperature. The lactam 3-Scheme-3 can be prepared from the carbodiimide 2-Scheme-3 by first condensing the carbodiimide 2-Scheme-3 with the desired xcex1-aminoester in a suitable organic solvent such as THF followed by removal of the TBS group using standard conditions such as TBAF in THF at 0xc2x0 C.